Nearly Single-Crystalline GaN Light-Emitting Diodes on Amorphous Glass Substrates
Journal
NAT PHOTONICS
Date
2011.10.10
Abstract
Single-crystalline gallium nitride (GaN)-based light-emitting diodes (s-LEDs) on crystalline
sapphire wafers can provide point-like light sources with high-conversion efficiency and long-
working lifetimes1-6. Recently, s-LEDs on silicon wafers have been developed in efforts to
overcome the size limitations of the sapphire substrate7. However, for applications to larger,
cheaper and efficient flat-light sources, fabrication of high-performance s-LEDs on amorphous
glass substrates would be required, which is still a scientific challenge.
Here we report the fabrication of nearly single-crystalline GaN on amorphous glass substrates in
the form of pyramid arrays. This was enabled by high-temperature GaN (HT-GaN) growth on the site-
confined nucleation layer with preferential polycrystalline morphology via local hetero-epitaxy
and predominant growth. InGaN/GaN multiple-quantum wells (MQWs) formed on the GaN pyramid arrays
exhibited high internal quantum efficiency of 52％. Furthermore, LED arrays fabricated using the
GaN pyramid arrays demonstrated reliable and stable area-type electroluminescent emission with a
luminance of 600 cd/m2.